Bore sight

ABSTRACT

A bore sight including a rear casing, a front casing sized to cooperatively engage the rear casing and define a first cavity and a separate second cavity, a laser disposed within the first cavity, and a battery in the second cavity. The bore sight further includes a switch selectively connecting the battery and the laser, an elongate mandrel releasably engaging the rear cavity, the mandrel having a free-end, a tapered seating collar having a through hole sized to receive a length of the mandrel, the seating collar being a separate components from the mandrel and the rear casing, wherein the seating collar can be formed of a different second material than the mandrel and the rear casing; and an adaptor releasably engaging a free end of the mandrel.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT.

Not applicable.

THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT.

Not applicable.

REFERENCE TO A “SEQUENCE LISTING”

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to identifying and projecting a beam ofradiation along a longitudinal axis of a bore of a gun, and moreparticularly, to a method and bore sight apparatus for identifying thelongitudinal axis of the bore with the beam of radiation for alignmentor calibration of corresponding gun sights.

2. Description of the Related Art

In “sighting in” guns, including firearms, such as rifles, shotguns,handguns, muzzle loaders, machine guns and cannons, it is necessary toadjust the sights of the gun at a pre-established angle with thelongitudinal axis of the bore of the barrel of the gun, where the angleis determined by the distance from the muzzle (open end of the bore) ofthe gun to the target, and by the trajectory of the bullet or projectilefired by the gun. In its most basic form, “sighting in” has beenaccomplished by mounting the gun on a fixed stand or in a fixed positionrelative to a “sighting in” target. The target was placed at the actual,final desired distance from the gun, and a test shot was fired. Thepoint on the target where the bullet or projectile entered the targetwas then aligned with the sight (whether iron sights or a telescopesight). After this was done, a second shot was fired; and the procedurewas repeated until the point of entry of the bullet or projectilealigned with the cross hairs or cross points of the sights. In manycases, a number of shots needed to be fired in order to effect thesighting in procedure.

For each different range or target distance, a separate “sighting in”procedure had to be followed. Thus, a significant amount of ammunitionwas expended simply to sight in the gun, and the “sighting in” needed tobe effected in a place where the firing of the actual bullet orprojectile from the firearm over the desired distance could be safelyaccomplished. The result was a relatively time consuming, costly andpotentially hazardous sighting in technique.

Certain prior devices for aligning the sights of a gun employ a laserdisposed within a cartridge, wherein the cartridge can be operablylocated in the breech of the gun. However, due to various tolerances,wear and the limited engagement between the cartridge and the breech,the cartridge may not seat in a sufficiently precise and repeatablemanner to provide for accurate alignment. In addition, as a givencartridge is only useful for a single corresponding caliber bore, aseparate cartridge is necessary for each caliber weapon.

Other prior bore sight configurations have employed a one-piece bodyconfigured to retain a laser, switch and battery as well as define acontact surface with the bore. However, such constructions do not allowfor optimization of material selection for contacting the bore, as wellas implementing a repeatable structure.

Therefore, the need exists for a bore sight which can have multiplecomponents, without sacrificing accuracy, wherein the material of theindividual components can be optimized for the intended operation of thebore sight. The need further exists for a compact bore sight which canbe readily adaptable to cooperatively engage any of a plurality ofcaliber guns.

BRIEF SUMMARY OF THE INVENTION

In one configuration, a bore sight is provided having a rear casing; afront casing sized to cooperatively engage the rear casing and define afirst cavity and a separate second cavity; a laser disposed within thefirst cavity, the laser selectively emitting a radiation beam along anoptical axis; a battery disposed in the second cavity; a switchselectively connecting the battery and the laser module; an elongatemandrel extending from the rear cavity, the mandrel having a free end; atapered seating collar having a through hole sized to receive a lengthof the mandrel, the seating collar formed of a different second materialthan the mandrel and the rear casing; and an adaptor releasably engagingthe free end of the mandrel.

It is contemplated that the bore sight can further include a coupler andan insert sized to cooperatively engage the front casing and the rearcasing in defining the first cavity and the second cavity.

The adaptor can include a flange seat fixed along a longitudinaldimension of the mandrel and a capture head threadedly engaging at leastone of the flange seat and the mandrel to vary a longitudinal distancebetween a portion of the capture head and the flange seat and themandrel to vary a longitudinal distance between a portion of the capturehead and the flange seat, and a resilient bushing longitudinallyintermediate the portion of the flange seat and the capture head.

A method is also provided for operably locating the bore sight within abore having a longitudinal axis by disposing a length of an elongatemandrel within a length of the bore; rotating a capture head relative tothe mandrel to decrease a longitudinal distance between the capture headand a flange seat and radially expand a bushing longitudinallyintermediate a portion of the capture head and the flange seat tocontact an inner surface of the bore at a contact area, a dimension ofthe contact area along the longitudinal axis being less than a diameterof the bore; and contacting a seating collar with an end of the bore,the seating collar of a different second material than the mandrel, tolocate a first cavity retaining a laser and a separate second cavityretaining a battery relative to the longitudinal axis, wherein the laseris substantially collinear with the longitudinal axis.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

FIG. 1 is a cross sectional view of a first configuration of the boresight.

FIG. 2 is an enlarged cross-sectional view of a portion of the boresight of FIG. 1.

FIG. 3 is an enlarged cross-sectional view of a housing portion of thebore sight of FIG. 1.

FIG. 4 is an enlarged cross-sectional view of an adapter employed in thebore sight of FIG. 1.

FIG. 5 is a cross sectional view of the bore sight operably engaged witha barrel having a bore.

FIG. 6 is a perspective view of an alternative configuration of the boresight.

FIG. 7 is a cross-sectional view of the bore sight of FIG. 6.

FIG. 8 is an enlarged cross-sectional view of a housing and switch ofthe bore sight of FIG. 6.

FIG. 9 is an enlarged cross-sectional view of a housing and switch ofthe bore sight of FIG. 8, with the switch in a different position.

DETAILED DESCRIPTION OF THE INVENTION

In FIG. 1, the present bore sight 10 generally includes a front casing20, a rear casing 60, an elongate mandrel 100, a seating collar 120, andan adaptor 140. As seen in FIG. 5, the bore sight 10 cooperates with abarrel 8 having a bore 7, wherein the barrel and bore terminate at anopen end and define a longitudinal axis.

The front casing 20 and the rear casing 60 cooperatively engage todefine a first cavity 21 and a separate second cavity 61, wherein thefirst cavity retains a laser module 30 and the second cavity retains atleast one of a battery 62 and a switch 64. As seen in FIGS. 2 and 3, acoupler 40 and an insert 50 can be retained between the front casing 20and the rear casing 60. By employing a separate front casing 20 and rearcasing 60, the casings can be individually manufactured allowing forless complicated tooling and manufacturing costs. Thus, the front casing20 and the rear casing 60 cooperatively engage to form a housing for atleast one of, and in selected configurations each of, the laser module30, the battery 62 and the switch 64. As seen in FIG. 5, the housing isat least substantially coaxial or concentric with the longitudinal axisof the barrel.

As seen in FIG. 3, the front casing 20 includes a generally cylindricalbody having a forward opening 23, a transverse alignment screw port 25,and a laser seat 26 projecting radially inward. The front casing 20 canbe made from polymers, metals, alloys and composites. A satisfactorymaterial has been found to include aluminum.

The forward opening 23 of the front casing 20 operably retains a lensmount 28. The lens mount 28 can include focusing and/or protectiveoptics for passing the laser along an exit axis. It is contemplated thefront casing 20 can include a retaining groove 29 for engaging acorresponding ridge of the lens mount 28, such that the lens mount 28can be changed out to provide for different properties of the generatedbeam.

The laser module 30 includes a laser 32 such as an LED laser, typicallyemitting in a visible wavelength. However, it is understood the laser 32of the laser module 30 can be selected to generate a beam in theinfrared or other non-visible range, thereby allowing the user, withappropriate viewing glasses, to align the gun. The laser 32 projects abeam of radiation along an optical axis.

The laser module 30 includes a radially extending flange 34 sized toengage the seat 26 of the front casing 20. In addition, the laser module30 includes an electrical contact 36 for receiving power for operatingthe laser 32. The electrical contact 36 can be in the form of a spring,such as a coil spring.

The front casing 20 also houses a bias member 38, such as a leaf springoperably disposed between a portion of the mounted laser module 30 andan inner surface of the front casing 20.

An alignment screw 39 is threadedly disposed within the alignment screwport 25 and contacts a portion of the laser module 30, such thatmovement of the laser module by the alignment screw is opposed by thebias member 38. Although the front casing 20 is shown with one alignmentscrew port 25, it is understood the front casing can include two, threeor more alignment screw ports with corresponding alignment screws forlocating an emission axis of the laser module 30 relative to the frontcasing 20.

The rear casing 60 cooperatively engages the front casing 20 to capturethe coupler 40 and the insert 50 such that the front casing and the rearcasing define the first cavity 21 and the separate second cavity 61.

As seen in FIG. 3, the coupler 40 can include an electrical lead 42extending between a first surface 44 exposed to the first cavity 21 anda second surface 46 exposed to a second cavity 61.

As seen in FIG. 3, the insert 50 cooperates with the coupler 40 and arespective portion of the front casing 20 and the rear casing 60 todefine the first cavity 21 and the separate second cavity 61.

The rear casing 60 includes a transverse aperture 63 accessing thesecond cavity 61. The second cavity 61 is sized to operably retain atleast one battery 62 and the switch 64 for selectively providing anelectrical input to the electrical lead on the coupler. As seen in FIG.3, the rear casing 60 includes a ramp 66 exposed to the second cavity61. In one configuration, the switch 64 is a rotation switch having acam surface 65 for engaging the ramp 66 in the rear casing 60. Thus,upon rotation of the switch 64 relative to the rear casing 60, theswitch cams into and out of contact with the rear casing, therebyresulting in the creation or breaking of electrical contact of thebatteries to the laser module 30.

A rear end of the rear casing 60 includes an aperture or recess 67 sizedto cooperatively receive a portion of the mandrel 100. The mandrel 100can be engaged with the rear casing 60 by any of a variety of mechanismsthat preclude rotation of the mandrel relative to the rear casing.Threaded engagements, friction fit, detents, adhesives or over-moldingcan be used to engage the mandrel 100 and the rear casing 60. Thus, themandrel 100 can be fixed relative to the rear casing 60, such thatrotation of the casing imparts rotation of the mandrel.

The rear casing 60 can be made from polymers, metals, alloys andcomposites. A satisfactory material has been found to include aluminum.It is understood that if the rear casing 60 is used as a portion of thecircuit interconnecting the battery 62 and the laser module 30, then anon-conductive material of the rear casing could include a conductivelead or trace.

The mandrel 100 is operably engaged with the rear casing 60 to disposethe seating collar 120 adjacent to the rear casing, wherein a free end102 of the mandrel is disposed a given distance from the rear casing.Referring to FIG. 4, the free end 102 of the mandrel 100 includes amechanism such as a recess and particularly a threaded recess 104 forcooperatively engaging the adapter 140.

The seating collar 120 defines a generally tapered (or stepped) outersurface 122 extending from a narrow end 124 to a flared end 126, andincludes a central through aperture 129 sized to receive a length of themandrel 100. An inner surface of seating collar 120 at the flared end126 defines an engaging surface 130 for engaging an outer surface of therear casing 60. Thus, the seating collar 120 defines a surface extendingfrom an outer surface of the mandrel 100 to extend beyond the diameterof the rear casing 60. In addition, referring to FIG. 2, the throughaperture 129 and the mandrel 100 can include cooperating ribs 132 andrecesses 133 to locate the seating collar 120 on the mandrel 100. Theseating collar 120 can cooperatively and releaseably engage at least oneof the mandrel 100 and the rear casing 60. As the seating collar 120 isremovably connected to at least one of the mandrel 100 and the rearcasing 60, the seating collar is interchangeable to accommodate variousranges of bore diameters (calibers), the seating collar can beconstructed to define a variety of lengths along the longitudinal axis,thus defining a corresponding variety of angles relative to thelongitudinal axis. That is, the angle of inclination between the outertapered surface 122 of the seating collar 120 and the longitudinal axisof the mandrel 100 can be varied for different bore diameters as well asfor a given bore diameter, by virtue of using a different seatingcollar. Satisfactory angles of the tapered surface 122 have been foundto include between approximately 5° and 45°.

In one configuration, the seating collar 120 is formed as a separatecomponent than the mandrel 100 and the rear casing 60. By separatelyforming the seating collar 120, the size of the stock necessary tomanufacture the bore sight 10 can be reduced. That is, rather thanforming the entire bore sight 10 from a block of sufficient size toencompass the seating collar 120, the separate components can be formedfrom stock of a size optimized for the given component. Further, formingthe seating collar 120 as a separate component allows the seating collarto be formed of a different second material than the mandrel 100,thereby allowing the mandrel to be formed of a durable lightweight metalsuch as aluminum, steel, or an alloy, wherein the seating collar can beformed of a polymer such as a thermoplastic, thermoplastic elastomer orthermoset material. Further, as the seating collar 120, can be formed ofa compliant or resilient material, the seating collar can frictionallyengage and retain the bore sight 10 relative to the open end of thebore, without imparting wear on the bore. The relative hardness of thematerial of the seating collar 120 is selected to avoid being socompliant that the desired alignment of the bore sight 10 within thebore is not achieved against being so hard that the bore can be damaged.A satisfactory hardness of the seating collar 120 has been found to beless than the barrel 8 and sufficiently great to retain the bore sight10 in an intended operable position.

The mandrel 100 extends to the free end 102, wherein the free endincludes the mechanism for receiving a portion of the adaptor 140.

The adaptor 140 includes a flange seat 150, a capture head 160, and anexpandable bushing 170, wherein the bushing is located longitudinallyintermediate a portion of the flange seat and the capture head.

The flange seat 150 contacts the free end 102 of the mandrel 100 andadjacent longitudinal portions of the mandrel and defines a generallycircular seat 152 extending radially outward for cooperatively engagingthe bushing 170. The flange seat 150 further includes a central aperture153 sized to pass a portion of the capture head 160 therethrough. Atleast one of the flange seat 150 and the recess 104 is threaded tocooperatively engage the capture head 160. In one configuration, theflange seat 150 rotates relative to the mandrel 100.

The circular seat 152 defines a shoulder 154 for engaging the bushing170 and precluding longitudinal movement of the bushing relative to theflange seat 150. The shoulder 154 can include a facet 156 perpendicularto the longitudinal axis and a facet 158 angled to the longitudinalaxis. In one configuration, the perpendicular facet 156 is radiallyintermediate the angled facet 158 and the longitudinal axis of themandrel 100.

The capture head 160 includes a bushing seat 162 and a projecting stem164 sized to cooperatively engage the mandrel 100. The bushing seat 162defines a shoulder 166 for engaging the bushing 170 and precludinglongitudinal movement of the bushing relative to the capture head 160.The shoulder 166 can include a facet 167 perpendicular to thelongitudinal axis and a facet 168 angled to the longitudinal axis. Inone configuration, the perpendicular facet 167 is radially intermediatethe angled facet 168 and the longitudinal axis of the mandrel 100.

The stem 164 can include threads for cooperatively engaging the mandrel100. However, it is understood that any of a variety of mechanisms couldbe used to engage the capture head 160 and the mandrel to decrease thelongitudinal distance between the capture head and the flange seat 150.The alternative mechanisms include cooperating magnets, bias memberssuch as springs, plungers or telescoping members.

The expandable bushing 170 includes engaging surfaces 172 forcooperatively engaging the corresponding portions of the flange seat 150and the capture head 160. In one configuration, the bushing 170 includesan annular groove 175 or line of preferential deformation longitudinallyintermediate the ends of the bushing. The line of preferentialdeformation 175 is configured such that upon longitudinal compression ofthe bushing 170 by relative motion of the capture head 160 relative tothe flange seat 150, the bushing flexes radially outward to form agenerally circular line of contact with the inside surface of the bore.The bushing 170 is selected such that line (or area) of contact haslongitudinal dimension that is less than the circumferential dimension,and advantageously substantially less than the circumferential dimensionof the bore. That is, for example in a 38 caliber gun, the bore hasdiameter of approximately 0.379 inches, and the line of the contactbetween the bushing 170 and the bore extends along the longitudinaldimension less than 0.379 inches, and advantageously less than 0.175inches, and can be as little as 0.15 inches. As the longitudinaldimension of the contact between the bushing 170 and the bore isreduced, the relative pressure at the resulting area of contactincreases, thereby securing retaining the bushing relative to thebushing as well as aiding in centering the longitudinal axis of themandrel 100 with the longitudinal axis of the bore.

In operation, as seen in FIG. 5, an appropriate seating collar 120 andadaptor 140 for the anticipated bore size are selected for cooperativeengagement with the mandrel 100.

The appropriate dimensioning or sizing of the seating collar 120 allowsthe tapered surface of the seating collar to engage the end of the bore.As the seating collar 120 can be formed of a polymeric material, theseating collar can repeatedly contact the bore as well as move relativeto the bore without imparting damage to the bore.

With respect to the adapter 140, the appropriate sizing allows theadaptor to be disposed along the inside of the bore until the seatingcollar 120 contacts the end of the bore. An outside surface of thebushing 170 contacts an inside surface of the bore 7, thereby at leastsubstantially precluding rotation of the bushing relative to the bore.Continued rotation (in the configuration employing the threadedconnection between the adapter 140 and the mandrel 100) of the front andthe rear casings 20, 60 cause the mandrel 100 to rotate relative to theflange seat 150 and thereby rotate the capture head 160 relative to themandrel and change the longitudinal distance between the flange seat andthe capture head. Further, the adaptor 140 is sized such that uponchanging, and particularly shortening, the longitudinal distance betweenthe capture head 160 and the flange seat 150, a radial dimension of thebushing 170 is increased and contacts the inner surface of the borealong an annular or circumferential contact, wherein the annular contacthas a reduced longitudinal dimension, thereby increasing the pressurebetween the bushing and the inside of the bore.

Actuation of the switch 64 in the second cavity 61 completes a circuitcausing current to flow from the batteries 62 along the electrical lead42 of the coupler 40 and to the spring contact with the laser module 30.

As the laser module 30 is operably aligned within the front casing 20,the emitted laser extends along an axis which is collinear with themandrel 100 and the lines of contact defined by the adaptor 140 and theseating collar 120.

The present configuration provides a number of advantages including theability to employ materials such as metal for formation of the mandrel100 and the casings 20, 60, wherein the contact with the bore can bedefined by relatively compliant material such as polymers,thermoplastics, and thermoplastic elastomers, while still providingsufficient contact with the bore to appropriately align the laser axiswith the longitudinal axis of the bore and thus permit alignment of thegun sights with the axis of the bore.

In addition, by concentrating the area of contact between the bushing170 of the adapter 140 and the inside of the bore, a more controlled andreproducible alignment of the bore sight and the bore can be achieved.

Referring to FIGS. 6-9, an alternative configuration of the bore sight10 is shown. In this configuration, the coupler 40 includes a firstsurface lead 47 and a second surface lead 49, wherein the switch 64selectively electrically interconnects the first surface lead and thesecond surface lead. In FIG. 7 the switch 64 is in an open position. Asseen in FIG. 8, the switch 64 is disposed in the closed or power onposition. In this alternative configuration, the switch is disposedabout an outside surface of the front casing and the rear casing.

The invention has been described in detail with particular reference toa presently preferred embodiment, but it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention. The presently disclosed embodiments are thereforeconsidered in all respects to be illustrative and not restrictive. Thescope of the invention is indicated by the appended claims, and allchanges that come within the meaning and range of equivalents thereofare intended to be embraced therein.

1. A bore sight for aligning with a barrel having a bore with an openend, the bore sight comprising: (a) a housing retaining a laser, abattery and a switch, the switch selectively connecting the battery andthe laser; (b) an elongate mandrel extending from the housing along alongitudinal axis, the mandrel having a free end; (c) a seating collarhaving a through hole sized to receive a length of the mandrel, theseating collar being a separate component from the mandrel and thehousing and removably connected to at least one of the housing and themandrel, the seating collar having a tapered outer surface sized toengage the open end of the bore; and (d) an adaptor engaging themandrel, the adapter having a variable dimension transverse to thelongitudinal axis.
 2. The bore sight of claim 1, wherein the housingincludes a bias member and an adjustment screw to modify orientation ofthe laser relative to the housing.
 3. The bore sight of claim 1, whereinthe elongate mandrel is fixedly connected to the housing.
 4. The boresight of claim 1, wherein the adaptor includes a flange seat fixed alonga longitudinal axis of the mandrel and a capture head, the capture headmoveable relative to the flange seat to vary a longitudinal distancebetween a portion of the capture head and the flange seat, and aresilient bushing longitudinally intermediate a portion of the flangeseat and the capture head.
 5. The bore sight of claim 4, wherein theflange seat threadingly engages the mandrel.
 6. The bore sight of claim1, wherein the adaptor includes a resilient expansion bushing, thebushing having a coefficient of friction sufficient to engage the barreland allow rotation of the housing relative to the barrel.
 7. The boresight of claim 1, wherein the seating collar is a different materialthan the mandrel.
 8. The bore sight of claim 1, wherein the seatingcollar is the same material as the mandrel.
 9. The bore sight of claim1, wherein the seating collar releaseably engages the mandrel and thehousing.
 10. The bore sight of claim 1, wherein the housing is co-axialwith a longitudinal axis of the barrel.
 11. A bore sight comprising: (a)a rear casing; (b) a front casing sized to cooperatively engage the rearcasing and define a first cavity and a separate second cavity; (c) alaser disposed within the first cavity, the laser selectively emitting aradiation beam along an optical axis; (d) a battery disposed in thesecond cavity; (e) a switch selectively connecting the battery and thelaser module; (f) an elongate mandrel extending from the rear cavityalong a longitudinal axis, the mandrel having a free end; (g) a taperedseating collar spaced from the free end of the mandrel; and (h) anadaptor engaging the mandrel, the adapter having a variable dimensiontransverse to the longitudinal axis.
 12. The bore sight of claim 11,further comprising a coupler and an insert sized to cooperatively engagethe front casing and the rear casing in defining the first cavity andthe second cavity.
 13. The bore sight of claim 11, wherein the frontcasing includes a bias member and an adjustment screw to modify theorientation of the optical axis relative to a longitudinal axis of thebore.
 14. The bore sight of claim 11, wherein the elongate mandrel isfixedly connected to the rear casing.
 15. The bore sight of claim 11,wherein the adaptor includes a flange seat fixed along a longitudinaldimension of the mandrel and a capture head, the capture head engagingthe mandrel to vary a longitudinal distance between a portion of thecapture head and the flange seat, and a resilient bushing longitudinallyintermediate the portion of the flange seat and the capture head.
 16. Amethod of operably locating the bore sight within a barrel having a boreextending along a longitudinal axis, the method comprising: (a)disposing a length of an elongate mandrel within a length of the bore;(b) longitudinally displacing a capture head relative to the mandrel todecrease a longitudinal distance between the capture head and a flangeseat and radially expand a bushing longitudinally intermediate a portionof the capture head and the flange seat to contact an inner surface ofthe bore at a contact area, a dimension of the contact area along thelongitudinal axis being less than a diameter of the bore; and (c)contacting a seating collar with an end of the bore.
 17. The method ofclaim 16, further comprising forming the seating collar as a separatecomponent from the mandrel.
 18. The method of claim 16, furthercomprising forming the seating collar of a different second materialthan the mandrel.
 19. The method of claim 16, connecting a housing tothe mandrel, the housing having a first cavity retaining a laser and aseparate second cavity retaining a battery, wherein the laser issubstantially collinear with the longitudinal axis.
 20. The method ofclaim 16, further comprising moving the laser relative to the firstcavity against a bias member.